Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
332 AM EDT Fri Jul 31 2020

Valid 00Z Sat Aug 01 2020 - 00Z Sat Aug 08 2020

Today's models and ensembles agree on a moderate to brisk trade
wind pattern through the period with showers favoring windward
terrain but with a few occasionally finding their way to leeward
locations.  Within the moderate to brisk range for trade strength,
the relatively lighter winds should be during the weekend when a
front well to the north of the state briefly weakens the surface
high.  Then the winds should be strongest around Tuesday-Wednesday
with perhaps a slightly weaker trend late next week.  Broadly
speaking guidance shows an increase of precipitable water values
over the course of the period.  One area of enhanced moisture
should pass south of the islands around Monday-Tuesday, with 00Z
GEFS/12Z ECMWF means having this moisture brush the Big Island to
a greater extent than the 00Z GFS/ECMWF.  Then a larger area of
moisture (precipitable water values of 1.50 inch or greater)
should reach the state mid-late week.  Both of these areas of
moisture may produce some increased rainfall from trade showers
but with totals likely to remain in the lighter half of the
spectrum. 

Rausch